HD643303x Hitachi, HD643303x Datasheet - Page 176

• Manufacturer Part Number: HD643303x
• Description: Hitachi Microcomputer
• Manufacturer: Hitachi

7.11 Port B
7.11.1 Overview
Port B is an 8-bit input/output port that is also used for TPC output (TP
(TIOCB
to the A/D converter. Port B has the same set of pin functions in all operating modes. Figure 7-20
shows the pin configuration of port B.
Pins in port B can drive one TTL load and a 30-pF capacitive load. They can also drive a darlington
transistor pair. Pins PB
7.11.2 Register Descriptions
Table 7-17 summarizes the registers of port B.
Table 7-17 Port B Registers
Address*
H'FFD4
H'FFD6
Note: * Lower 16 bits of the address.
4
, TIOCB
Name
Port B data direction register
Port B data register
Port B
3
, TIOCA
3
to PB
4
, TIOCA
Figure 7-20 Port B Pin Configuration
0
have Schmitt-trigger inputs.
Port B pins
PB (input/output)/TP
PB (input/output)/TP
PB (input/output)/TP
PB (input/output)/TP
PB (input/output)/TP
PB (input/output)/TP
PB (input/output)/TP
PB (input/output)/TP
7
6
5
4
3
2
1
0
3
) and ITU output (TOCXB
161
Abbreviation
PBDDR
PBDR
15
14
13
12
11
10
9
8
(output)/ADTRG (input)
(output)
(output)/TOCXB (output)
(output)/TOCXA (output)
(output)/TIOCB (input/output)
(output)/TIOCA (input/output)
(output)/TIOCB (input/output)
(output)/TIOCA (input/output)
4
, TOCXA
15
R/W
W
R/W
to TP
4
4
3
3
4
4
4
), and ADTRG input
8
), ITU input/output
Initial Value
H'00
H'00